FIG. 1 is a schematic diagram of a conventional turbine control system in commercial nuclear power stations. As shown in FIG. 1, a turbine 100 receives source steam 101, extracts thermodynamic energy from the source steam 101, and outputs lower-pressure, saturated steam 102. Source steam 101 may be from a nuclear reactor, a heat exchanger, a steam generator, a higher-pressure turbine etc. Turbine 101 may be any turbine found in nuclear power plants, including a lower-output Reactor Core Isolation Cooling (RCIC) turbine or higher-output High Pressure Injection Cooling (HPIC) turbine, for example. The extracted energy 105 is used to power desired components; for example, in the case of an RCIC and HPIC, extracted energy 105 provides power to associated RCIC and HPIC cooling pumps that maintain flow and water levels in a reactor.
When a turbine 100 is used to run cooling systems to maintain reactor coolant levels and remove decay heat from the plant, such as in a transient scenario, turbine 100 is controlled by a speed controller 60. Turbine 100 generates speed information based on load and output and transmits speed information signals 61 to speed controller 60. Speed controller 60 generates speed control signals 62 based on received speed information signals 61 to be transmitted back to turbine 100. Speed information signals 61 permit turbine 100 to operate at specified speeds and loads to avoid tripping and provide adequate power 105 to desired destinations. Speed controller 60 is conventionally networked with a flow controller 55 in the plant control room, which exchanges flow control signals 56 with the speed controller 60. In this way, plant operators may monitor and input speed commands through the control room flow controller 55 that are translated into speed control signals 62 by speed controller 60 and ultimately control turbine 100 to perform in accordance with control room commands.
Control room flow controller 55 and speed controller 60, and data and signals generated thereby, are conventionally powered by offsite or plant power. As shown in FIG. 1, when such power is unavailable, such as during a station blackout event, a plant emergency power distribution source 50, such as a local diesel generator or battery, may provide electrical output 51 to control room flow controller 55 and speed controller 60. By offering local power, emergency power distribution source 50 may permit operators to continuously control a speed of and use turbine 100 to manage the transient and/or provide power to safety systems, including Core Isolation and High Pressure Injection Cooling pumps.